Monkey-wrench



(No Model.)

VLJ. McDONNF-LL.v

' MONKEY WRENCH.

No. 449,129. Patented Mar. 31, 1891.

ilnrrn STATES ATENT Erica.

MONKEY-WRENCH.

SPECIFICATION forming part of Letters Patent No. 449,129, dated March 31, 1891.

Application filed May 12, 1890- Serial No. 351,431. (No model.)

To all whom it may concern.-

Be it known that I, VINCENT J. MCDON- NELL, of the city of Philadelphia and State of Pennsylvania, have invented a certain new and useful Improvement in Monkeyrenches; and I do hereby declare the following to be afull, clear, and exact description thereof, reference being had to the accon'ipanying drawings, forming part of this specification.

My invention has relation to that class of wrenches known as monkey-wrenches, and it consists in the construction and novel arrangement of parts, as hereinafter particularly described.

My invention has for its object to provide a simple and effective wrench at asmall cost of that class of wrenches in which a mutilated screw is employed to allow of the ready adj ustment of the movable jaw and the locking of the same readily at any point desired by a simple turn of the mutilated screw, the threads of the screw engaging in the screwthreads provided in a longitudinal groove in the main shank of the wrench.

In this improved form of wrench, as hereinafter particularly described, I do away with all pawl locking devices, and thus not only reduce the cost of construction, but at the same time produce a wrench as effective as those in which the pawl devices are employed, with fewer parts, and the liability to get out of order reduced to a minimum.

In the accompanying drawings, similar letters of reference refer to similar parts throughout.

Figure l is a side elevation of a monkeywrench having my improvement, showing the mutilated side of the mutilated screw with the lever up. Fig. 2 is a longitudinal sectional view of the same with the leverdepressed to the right. Fig. 3 is a cross-sectional view on the line 68 w of Fig. 1. Fig. 4 is a cross-sectional view on line a: a" of Fig. 1, but with the lover of the mutilated screw depressed to the left, the mutilated part of the threads being down, and consequently the threads of the screw disengaged from the screw-threaded groove provided in the main shank.

A represents the main shank of the wrench, provided with a handle it and a fixed jaw a. Upon the main shank A the movable jaw a is adapted to slide and is movably secured thereon. Thespindle or rod B is provided on its inner end with a screw-thread s, which is screwed into a thread provided in themovable jaw a, as shown in the drawings, and has at the inner end of the handle h a bearingj. On the rod B is fixedly secured the mutilated screw 0, the'threads of which are adapted to become engaged or disengaged at will in the screw-threaded groove a provided in the main shank A. A small plate or lever Z is secured to the mutilated screw 0, as shown, to facilitate the adjustment of the mutilated screw 0. The rod B is elongated, as shown, so that it shall at all times have a bearing in the journal j, as when the movable jaw a is adjusted closely up to the fixed jaw a, and for a further object that when desirable or necessary the rod B may be held by the hand or fingers of the hand, at the same time while holding the wrench to prevent the mutilated screw 0 from turning and becoming disengaged from the screw-threaded groove a To further this end, the end of the rod B is preferably milled, as shown.

-When the movable jaw is adjusted to its proper position to fit a nut desired to be turned, the threads of the mutilated screw 0 are engaged in the threads of the screwthreaded groove a by simply turning the lever Z from the position shown in Fig.4to any of the positions shown in the other figures. If the position of the leverl is such as to render it liable to drop, so that the thread should become disengaged, the milled end of the rod B is grasped by the thumb or fingers of the hand holding the wrench and thus prevented from becoming disengaged. The screwthreads 3, provided on the end of the rod B, are of a reversed trend to the threads of the mutilated screw 0, so that as the mutilated screw C is turned toward the right the threads 3 assist the mutilated screw C in forcing the movable jaw a closely up upon the nut to be turned. I preferably employ a relative proportion of five threads to the inch in the mutilated-screw threads 0 to ten threads to the inch in the screw 3, the threads of the screw 5 beingpreferablyadouble thread.

By my construction, as shown, the several threads of the mutilated screw 0 have a steady even bearing in the threads of the ICO groove (0' by having bearings at both ends through the medium of the rod 1;. Pressure on the movable jaw a has a tendency where there is no end bearing, as at j, to create an uneven pressure on the threads and thereby to wear the same and render them liable to slip.

I am aware that mutilated screws in monkcy-wrenches for the purpose of facilitating the adjustment of the movable jaw and securing the same, where desired, are not new, and I do not claim the same broadly; but my invention resides in the construction as herein particularly described.

Having thus described my invention, what I claim, and desire to seeu re by Letters Patent, 1s-

1. In a wrench, in combination with a main shank having a screwthreaded longitudinal groove and a fixed jaw, a movable jaw movable on the main shank, a spindle or red provided at one end with a screu thread screwed into the movable jaw, said rod parallel with the main shank and jonrnaled thereto in a fixed journal-bearing, said rod adapted to slide to and fro when the mutilated screw is disengaged, movable horizontally and rotativel in the said journal-bearing, a mutilated screw, and a lever fixedly rovided on said rod adapted to turn the said rod when rotated and to turn the screw on the end of the said rod in the screw-th reads provided on the movable jaw, in the manner and for the purpose substan t ially as herei nbefore set forth and described.

2. In a wrench, the combination of the shank A, fixed jaw a, the movable jaw a, screw-threaded groove C62, provided lon git udinally in the main shank A, the rod B, journaled in a fixed journal-bearing parallelwith tho'main shank A, provided on its inner end with a screw-thread s, screwed into screwthreads provided in movable jaw a, mutilated screw 3, secured on rod 13, adapted to slide to and fro when the mutilated screw is disengaged, a lever Z, adapted to rotate the said mutilated screw 1, and rod B, substantially as hereinbefore set forth and described.

In witness whereof I have hereunto set my hand this 7th day of May, A. D. 1890.

VINCENT .I. MCDONNlGlJlJ. ilt'itnesses:

M. L. NEVIN, HORACE Pn'r'rrr. 

